Material: glass
Specification: square 32*32*1mm
Functions and characteristics of filter
Filter is an optical device used to select the required radiation band. A common feature of filters is that no filter can make the imaging of celestial bodies brighter, because all filters will absorb certain wavelengths, making objects darker. Optical filters play an important role and are widely used in photography.
Function of optical filter: filter plays a great role and is widely used in photography. Why is the main scene always so prominent in the landscape paintings taken by some shooting masters? How do you do it? Because of the use of filters. For example, if you want to shoot a yellow flower with blue sky and green leaves as the background, you can`t highlight the theme of ``yellow flower`` because the image of yellow flower is not prominent enough. However, if a yellow filter is installed in front of the lens to block the green light emitted by some green leaves, the blue light emitted by the blue sky, and let a large number of yellow light emitted by yellow flowers pass through, the yellow flowers will be very obvious and highlight the theme of ``yellow flowers``.
The filter is made of plastic or glass with special dyes. The red filter can only let the red light pass through, and so on. The refractive index of glass sheet is similar to that of air, and all color light can pass through, so it is transparent. However, after dyeing with dye, the molecular structure changes, the refractive index also changes, and the passage of some color light changes. For example, when a white light passes through a blue filter, it emits a blue light, while there are very few green and red light, and most of them are absorbed by the filter.
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